New explosions have been heard in Baghdad, as U.S. military officers report heavy fighting with Iraqi forces around Najaf to the south.

The blasts in the Iraqi capital were heard shortly after nightfall Wednesday and again later in the evening. Coalition aircraft bombed several targets in Baghdad earlier in the day, and knocked Iraqi satellite television off the air for several hours.

Iraqi officials say two U.S. missiles struck a Baghdad residential area, killing at least 14 people and wounding more than 30 others.

But a Pentagon official tells VOA that it was not a U.S. missile that hit the area because he said the type of precision-guided weapon used against targets in Baghdad Wednesday was not the type that could have gone astray.

The official also said the area was not among nine targeted Baghdad neighborhoods where the military has placed anti-aircraft sites.

He said there was a considerable amount of Iraqi anti-aircraft fire at the time of the casualties, suggesting it was an Iraqi missile that struck the civilians, or a deliberate bombing intended to look like a U.S. weapon.

The official said the Baghdad neighborhood is heavily populated with Shiite Muslims, who lead the Iraqi opposition in the south. The Pentagon says Saddam Hussein's decision to place military targets in residential neighborhoods shows he does not care about the Iraqi people. Wednesday's fighting near the city of Najaf, south of Baghdad, appears centered on a bridge over the Euphrates River. U.S. officials say Iraqi forces attacked elements of the U.S. Army's 7th Cavalry regiment with rocket-propelled grenades as it was moving across the bridge.

U.S. military officers say the attack destroyed a number of U.S. tanks and Bradley fighting vehicles. But they say U.S. forces have killed at least several hundred Iraqi soldiers in fighting at the bridge and elsewhere around Najaf since early Tuesday.

There are several reports of a convoy of Iraqi Republican Guard vehicles heading south from Baghdad. U.S. Central Command said there has been no sign of any such large-scale movement.

Coalition forces remain at Karbala, about 90 kilometers south of Baghdad, while to the southeast, several thousand U.S. Marines advanced Wednesday to the town of Shatra, 275 kilometers from Baghdad. There they ran into more Iraqi resistance.